Hypertrophic Cardiomyopathy - Exams and Tests

Exams and Tests

Hypertrophic cardiomyopathy can be difficult to diagnose because it may not always cause symptoms. The first step in diagnosing heart problems is a thorough medical history and physical exam.

Your doctor will ask you about any family history of hypertrophic cardiomyopathy or any heart disease. Your doctor will also want to know if any relatives died an early and sudden death. Sometimes when young people die of cardiac arrest from hypertrophic cardiomyopathy, the disorder is not discovered because autopsies are not always performed.

During the physical exam, your doctor will listen to your heart with a stethoscope. If any extra or unusual heart sounds (gallops or murmurs) are heard, it may mean the structure of the heart is abnormal.

You will usually have one or more of the following tests to help your doctor diagnose and treat your condition.

Electrocardiogram

An electrocardiogram (ECG or EKG) measures the electrical activity as it moves through the heart during contraction and relaxation. An abnormal electrocardiogram may be the first sign of hypertrophic cardiomyopathy in people who do not have any symptoms.

Echocardiogram

An echocardiogram (echo) is a type of ultrasound exam that uses high-pitched sound waves to create an image of the heart, which is seen on a television screen. An echo is the main tool used to help doctors diagnose hypertrophic cardiomyopathy and its severity.

Echocardiography can be used to:

• Estimate how well the lower left chamber of the heart (left ventricle) is able to fill when the heart expands and measure how much blood is pumped out as it contracts (ejection fraction).
• Determine if the heart valves are functioning normally.
• Measure overall heart size.
• Determine if the heart muscle (myocardium), including the wall that separates the left and right chambers of the heart, is unusually thick.
• Measure the degree that blood flow is reduced during contraction (systole) if the wall that separates the left and right chambers of the heart is abnormally thick.

Physical exam, electrocardiogram, and echocardiogram are the best ways to diagnose hypertrophic cardiomyopathy. People with a family history of sudden death, especially young athletes or those who are considering starting an exercise program, should talk to their doctor about being tested for hypertrophic cardiomyopathy. These tests may also help evaluate a person who faints during strenuous physical activity.

Patients who are considered to be low risk will not see their doctor as often as patients considered at high risk, usually around every 3 years. An echocardiogram is usually done again if your symptoms change or get worse.

Exercise test

Your doctor may have you run on a treadmill or pedal a stationary bike while he or she looks at how well your heart and lungs are working. An exercise test can give the doctor (and you) an idea of how hard and how long you can exercise.

The results of an exercise test may show that you have a higher risk for serious health problems due to hypertrophic cardiomyopathy. Some doctors recommend an exercise test before beginning any treatment for hypertrophic cardiomyopathy.

Chest X-ray

A chest X-ray produces a photographic image of the heart using rays of intense light energy that pass through the body and project an image on a film. An X-ray can show information about the heart's size and shape. In later stages of hypertrophic cardiomyopathy, an X-ray may reveal signs of pulmonary edema, which is fluid buildup in the lungs.

Cardiac catheterization (cardiac cath) or coronary angiography

During a cardiac catheterization or coronary angiogram, a long, thin tube (catheter) is threaded through an artery or vein in the arm or groin and into the heart to measure pressure in the heart chambers. Dye can be injected through the catheter to see whether the coronary arteries are blocked, how well the heart chambers are pumping, and whether heart valves are leaking.

Angiography may be done if the results of the echocardiogram are inadequate. Angiography may also be used to check if surgery would be an option for treatment of hypertrophic cardiomyopathy.

Genetic testing

Genetic testing can identify some genes that are related to this condition. Many people who have relatives with hypertrophic cardiomyopathy wonder if they or their children should have genetic testing. So far, routine genetic testing is not yet practical because there are so many possible abnormal genes that cause the disease. Genetic testing is presently used in a small number of cases when the specific genetic mutation in the affected relative has been identified.